Ventana software support forum

No (except perhaps for some complex tricks). What are you trying to do?

Not following this ... if variable #2 only has an initial value, how can new values be measured?

Definitely - percent is important because it's easy to inadvertently mix % and fractions. Define a variable called "100 percent" with units of "percent" and use that to convert between the two. Something like: "100 percent" == 100 ~ percent birth rate = 2.3 ~ percent/year fractional birth rate = bir...

The word "count" implies "stock". You can do something like the following: count = INTEG( counting, 0 ) counting = start of cycle/TIME STEP start of cycle = {logical flag - a function of your process} The trick is to avoid counting the same cycle in consecutive TIME STEPS, but it's hard to say more ...

What you choose depends on what you need to represent - if you're modeling an accounting process explicitly, the pulsed or delayed reporting stock is good. If you're just capturing the natural delay and smoothing in a perception process, it's much simpler to use a SMOOTH or SMOOTH3 function. Reporti...

You can use a stock to keep track of this. Make the inflow the current death rate, and the outflow equal to a DELAY FIXED of the same rate, with a time constant of one year (in whatever units your model is using).

See the sample model at the end of viewtopic.php?f=2&t=6892 (April 18).

Here are three different parameterizations, using terminology from NIST, Wikipedia and Wolfram Mathworld:

Try the sample model attached to the help system topic for the random functions. It's in c:\users\public\vensim if your OS won't let the help link work.

Terminology for the Weibull distribution is not well standardized, and most sources don't use alpha and beta. Can you give us a reference you're trying to match?

It sounds like you're running a chain of models, where the output from one is the input to the next. This is easy with a command script (requires Vensim DSS).

I assume you mean this? https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1939-7445.2009.00058.x The paper is paywalled, but I'm going to speculate that in general it would be tricky to implement. You'd have to have a library of functions with desired properties that meet all the reality checks need...

If you're using GET XLS, it can only handle one dimension (plus time) at a time. So, you'd need three equations to import this: data[USA,importCountries] = GET XLS DATA( ... , 'C5' ) data[Germany,importCountries] = GET XLS DATA( ... , 'C8' ) data[China,importCountries] = GET XLS DATA( ... , 'C11' ) ...

Great - hopefully things can move forward now.

This is a working merger (it parses and runs, but crashes with an fp error pretty quickly). I had to modify the equations differently - modifying the host global model's j and k ranges rather than the biogeochem model.

Was the modified BIOGEOCHEM model runnable before you attempted the paste? It appears that it uses a lot of individual subscript elements in the equations, so it would be nontrivial to rename the elements.

I think part of the problem may be that you have j and k ranges in both models, presumably with different ranges and interpretations. Since the biogeochem model is simpler, I'd rename all the ranges, subranges and elements there before doing the copy/paste. In any case, i, j, k etc. would usually be...

When you paste across models, Vensim generally tries to bring the needed subscript families along. However, if there are overlapping names of elements, ranges or subranges, this may cause a conflict. I think that might be what's happened here. When I look at the subscript control in my copy (in 7.3....

I can open the model using File>Edit File to bring it into the text editor. There seem to be a lot of subscript errors: ERROR: Unspecified subscript equation for - j10. ERROR: Unspecified subscript equation for - j11. ERROR: Unspecified subscript equation for - j12. ERROR: Unspecified subscript equa...

Do you have an earlier, working version we can compare?

Try the samples in the help system: http://vensim.com/documentation/usr15.htm

What is shown on this plot? If it's a parameter, it will be constant.

Right-click the sensitivity graph tool and change the options to show confidence bounds rather than individual traces.

From your second graph, it looks like the range of behavior is very narrow.

Or just Tools>Analysis>New to reload a new copy of the toolset.